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Full-Text Articles in Life Sciences
Mitochondrial Oma1 And Opa1 As Gatekeepers Of Organellar Structure/Function And Cellular Stress Response, Robert Gilkerson, Patrick De La Torre, Shaynah St. Vallier
Mitochondrial Oma1 And Opa1 As Gatekeepers Of Organellar Structure/Function And Cellular Stress Response, Robert Gilkerson, Patrick De La Torre, Shaynah St. Vallier
Biology Faculty Publications and Presentations
Mammalian mitochondria are emerging as a critical stress-responsive contributor to cellular life/death and developmental outcomes. Maintained as an organellar network distributed throughout the cell, mitochondria respond to cellular stimuli and stresses through highly sensitive structural dynamics, particularly in energetically demanding cell settings such as cardiac and muscle tissues. Fusion allows individual mitochondria to form an interconnected reticular network, while fission divides the network into a collection of vesicular organelles. Crucially, optic atrophy-1 (OPA1) directly links mitochondrial structure and bioenergetic function: when the transmembrane potential across the inner membrane (ΔΨm) is intact, long L-OPA1 isoforms carry out fusion of the mitochondrial …
Mitochondrial Opa1 Cleavage Is Reversibly Activated By Differentiation Of H9c2 Cardiomyoblasts, Iraselia Garcia, Fredy Calderon, Patrick De La Torre, Shaynah St. Vallier, Cristobal Rodriguez, Divya Agarwala, Megan Keniry, Wendy Innis-Whitehouse, Robert Gilkerson
Mitochondrial Opa1 Cleavage Is Reversibly Activated By Differentiation Of H9c2 Cardiomyoblasts, Iraselia Garcia, Fredy Calderon, Patrick De La Torre, Shaynah St. Vallier, Cristobal Rodriguez, Divya Agarwala, Megan Keniry, Wendy Innis-Whitehouse, Robert Gilkerson
Biology Faculty Publications and Presentations
Optic atrophy-1 (OPA1) is a dynamin-like GTPase localized to the mitochondrial inner membrane, playing key roles in inner membrane fusion and cristae maintenance. OPA1 is regulated by the mitochondrial transmembrane potential (Δψm): when Δψm is intact, long OPA1 isoforms (L-OPA1) carry out inner membrane fusion. Upon loss of Δψm, L-OPA1 isoforms are proteolytically cleaved to short (S-OPA1) isoforms by the stress-inducible OMA1 metalloprotease, causing collapse of the mitochondrial network and promoting apoptosis. Here, we show that L-OPA1 isoforms of H9c2 cardiomyoblasts are retained under loss of Δψm, despite the presence of OMA1. However, when H9c2s are differentiated to a more …